Question

A diode is connected to $220\text{V}$(rms) AC in series with a capacitor, as shown in figure. The voltage across the capacitor is

• A. $220\text{V}$
• B. $110\text{V}$
• C. $311.1\text{V}$
• D. $\frac{220}{\sqrt{2}}\text{V}$

Answer 1

The correct option is D $\frac{220}{\sqrt{2}}\text{V}$

The diode D will conduct only during positive half cycle of a.c. supply, because it will be forward biased. For negative half cycle of a.c. supply, it will be reverse biased and will not conduct. So the output would be half wave rectified, and, for half wave rectified output,

$V_{rms}=\frac{V_0}{2}=\frac{220\sqrt{2}}{2}=\frac{220}{\sqrt{2}}\text{V}$

Hence, $\left(D\right)$ is the correct answer.